diff --git a/packed_struct/Cargo.toml b/packed_struct/Cargo.toml
index 94f74df..8b68e35 100644
--- a/packed_struct/Cargo.toml
+++ b/packed_struct/Cargo.toml
@@ -3,7 +3,7 @@ name = "packed_struct"
 description = "Binary-level structure packing and unpacking generator"
 repository = "https://github.com/hashmismatch/packed_struct.rs"
 homepage = "http://www.hashmismatch.net/libraries/packed-struct/"
-version = "0.10.1"
+version = "0.11.0"
 rust-version = "1.51"
 authors = ["Rudi Benkovic <rudi.benkovic@gmail.com>"]
 license = "MIT OR Apache-2.0"
@@ -13,7 +13,7 @@ readme = "../README.md"
 edition = "2018"
 
 [dependencies]
-packed_struct_codegen = { path = "../packed_struct_codegen/", version = "0.10.1" }
+packed_struct_codegen = { path = "../packed_struct_codegen/", version = "0.11.0" }
 serde = { version = "1.0", optional = true, default-features = false }
 serde_derive = { version = "1.0", optional = true }
 bitvec = { version = "0.22.3", default-features = false }
diff --git a/packed_struct/src/lib.rs b/packed_struct/src/lib.rs
index 833a200..6f76e30 100644
--- a/packed_struct/src/lib.rs
+++ b/packed_struct/src/lib.rs
@@ -272,7 +272,7 @@
 //! ```rust
 //! use packed_struct::prelude::*;
 //!
-//! #[derive(PrimitiveEnum, Clone, Copy, PartialEq, Debug)]
+//! #[derive(PrimitiveEnum_u8, Clone, Copy, PartialEq, Debug)]
 //! pub enum ImplicitType {
 //!     VariantMin = 0,
 //!     VariantMax = 255
@@ -377,7 +377,6 @@ pub use self::packing::*;
 /// The derivation macros for packing and enums.
 pub mod derive {
     pub use packed_struct_codegen::PackedStruct;
-    pub use packed_struct_codegen::PrimitiveEnum;
     pub use packed_struct_codegen::{PrimitiveEnum_u8, PrimitiveEnum_u16, PrimitiveEnum_u32, PrimitiveEnum_u64};
     pub use packed_struct_codegen::{PrimitiveEnum_i8, PrimitiveEnum_i16, PrimitiveEnum_i32, PrimitiveEnum_i64};
 }
diff --git a/packed_struct_codegen/Cargo.toml b/packed_struct_codegen/Cargo.toml
index 77ede43..0e53e67 100644
--- a/packed_struct_codegen/Cargo.toml
+++ b/packed_struct_codegen/Cargo.toml
@@ -2,7 +2,7 @@
 name = "packed_struct_codegen"
 description = "This crate implements the code generation for the packed_struct library."
 repository = "https://github.com/hashmismatch/packed_struct.rs"
-version = "0.10.1"
+version = "0.11.0"
 license = "MIT OR Apache-2.0"
 authors = ["Rudi Benkovic <rudi.benkovic@gmail.com>"]
 edition = "2018"
diff --git a/packed_struct_codegen/src/lib.rs b/packed_struct_codegen/src/lib.rs
index 3c6b1ce..cec678f 100644
--- a/packed_struct_codegen/src/lib.rs
+++ b/packed_struct_codegen/src/lib.rs
@@ -36,55 +36,48 @@ pub fn derive_packable_bytes(tokens: TokenStream) -> TokenStream {
         .into()
 }
 
-/// A derive macro that generates packing and unpacking code for simple enum variants.
-/// It helps with converting your enums into integer types and back, with many other helper
-/// traits.
-#[proc_macro_derive(PrimitiveEnum)]
-pub fn derive_primitive_detect(input: TokenStream) -> TokenStream {
-    derive_primitive(input, None)
-}
 
 #[proc_macro_derive(PrimitiveEnum_u8)]
 pub fn derive_primitive_u8(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("u8").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("u8").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_u16)]
 pub fn derive_primitive_u16(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("u16").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("u16").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_u32)]
 pub fn derive_primitive_u32(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("u32").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("u32").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_u64)]
 pub fn derive_primitive_u64(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("u64").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("u64").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_i8)]
 pub fn derive_primitive_i8(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("i8").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("i8").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_i16)]
 pub fn derive_primitive_i16(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("i16").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("i16").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_i32)]
 pub fn derive_primitive_i32(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("i32").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("i32").unwrap())
 }
 
 #[proc_macro_derive(PrimitiveEnum_i64)]
 pub fn derive_primitive_i64(input: TokenStream) -> TokenStream {
-    derive_primitive(input, Some(syn::parse_str::<syn::Type>("i64").unwrap()))
+    derive_primitive(input, syn::parse_str::<syn::Type>("i64").unwrap())
 }
 
-fn derive_primitive(input: TokenStream, ty: Option<syn::Type>) -> TokenStream {
+fn derive_primitive(input: TokenStream, ty: syn::Type) -> TokenStream {
     let input = parse_macro_input!(input as DeriveInput);
 
     primitive_enum::derive(&input, ty)
diff --git a/packed_struct_codegen/src/pack.rs b/packed_struct_codegen/src/pack.rs
index 0cd549e..2129b56 100644
--- a/packed_struct_codegen/src/pack.rs
+++ b/packed_struct_codegen/src/pack.rs
@@ -13,7 +13,7 @@ pub struct FieldMidPositioning {
 pub enum FieldKind {
     Regular {
         ident: syn::Ident,
-        field: FieldRegular
+        field: Box<FieldRegular>
     },
     Array {
         ident: syn::Ident,
diff --git a/packed_struct_codegen/src/pack_codegen_docs.rs b/packed_struct_codegen/src/pack_codegen_docs.rs
index 5c8b46b..1deb17b 100644
--- a/packed_struct_codegen/src/pack_codegen_docs.rs
+++ b/packed_struct_codegen/src/pack_codegen_docs.rs
@@ -35,7 +35,7 @@ pub fn struct_runtime_formatter(parsed: &PackStruct) -> syn::Result<proc_macro2:
             },
             FieldKind::Array { ref ident, ref elements, .. } => {
                 for (i, field) in elements.iter().enumerate() {
-                    let name_str = format!("{}[{}]", ident.to_string(), i);
+                    let name_str = format!("{}[{}]", ident, i);
                     let bits: syn::ExprRange = syn::parse_str(&format!("{}..{}", field.bit_range.start, field.bit_range.end))?;
                     
                     debug_fields.push(quote! {
@@ -136,7 +136,7 @@ pub fn type_docs(parsed: &PackStruct) -> proc_macro2::TokenStream {
                 },
                 FieldKind::Array { ref ident, ref elements, .. } => {
                     for (i, field) in elements.iter().enumerate() {
-                        emit_field_docs(&field.bit_range, format!("{}[{}]", ident.to_string(), i), &field.ty);
+                        emit_field_docs(&field.bit_range, format!("{}[{}]", ident, i), &field.ty);
                     }
                 }
             }            
diff --git a/packed_struct_codegen/src/pack_parse.rs b/packed_struct_codegen/src/pack_parse.rs
index 7b65891..eb211b6 100644
--- a/packed_struct_codegen/src/pack_parse.rs
+++ b/packed_struct_codegen/src/pack_parse.rs
@@ -205,7 +205,7 @@ fn parse_field(field: &syn::Field, mp: &FieldMidPositioning, bit_range: &Range<u
         syn::Type::Path(_) => {
             return Ok(
                 FieldKind::Regular {
-                    field: parse_reg_field(field, &field.ty, bit_range, default_endianness)?,
+                    field: Box::new(parse_reg_field(field, &field.ty, bit_range, default_endianness)?),
                     ident: field.ident.clone().ok_or_else(|| syn::Error::new(field.span(), "Missing ident!"))?
                 }
             );
@@ -468,7 +468,7 @@ pub fn parse_struct(ast: &syn::DeriveInput) -> syn::Result<PackStruct> {
                 },
                 FieldKind::Array { ref ident, ref elements, .. } => {
                     for (i, field) in elements.iter().enumerate() {
-                        find_overlaps(format!("{}[{}]", ident.to_string(), i), &field.bit_range)?;
+                        find_overlaps(format!("{}[{}]", ident, i), &field.bit_range)?;
                     }
                 }
             }
diff --git a/packed_struct_codegen/src/pack_parse_attributes.rs b/packed_struct_codegen/src/pack_parse_attributes.rs
index b2ae419..28a545c 100644
--- a/packed_struct_codegen/src/pack_parse_attributes.rs
+++ b/packed_struct_codegen/src/pack_parse_attributes.rs
@@ -187,7 +187,7 @@ pub fn parse_position_val(v: &str, multiplier: usize) -> Result<BitsPositionPars
         let n = parse_num(&v)?;
         return Ok(BitsPositionParsed::Start(n * multiplier));
     } else if v.ends_with(':') {
-        let v = v.replace(":", "");
+        let v = v.replace(':', "");
         let n = parse_num(&v)?;
         return Ok(BitsPositionParsed::Start(n * multiplier));
     } else if v.contains(':') || v.contains("..=") {
diff --git a/packed_struct_codegen/src/primitive_enum.rs b/packed_struct_codegen/src/primitive_enum.rs
index ca207f2..25e3e78 100644
--- a/packed_struct_codegen/src/primitive_enum.rs
+++ b/packed_struct_codegen/src/primitive_enum.rs
@@ -7,7 +7,7 @@ use syn::spanned::Spanned;
 use crate::utils::*;
 use crate::common::collections_prefix;
 
-pub fn derive(ast: &syn::DeriveInput, mut prim_type: Option<syn::Type>) -> syn::Result<proc_macro2::TokenStream> {
+pub fn derive(ast: &syn::DeriveInput, prim_type: syn::Type) -> syn::Result<proc_macro2::TokenStream> {
 
     let stdlib_prefix = collections_prefix();
 
@@ -15,10 +15,11 @@ pub fn derive(ast: &syn::DeriveInput, mut prim_type: Option<syn::Type>) -> syn::
     let v = get_unitary_enum(ast)?;
 
     let from_primitive_match: Vec<_> = v.iter().map(|x| {
-        let d = x.get_discriminant();
         let n = &x.variant.ident;
         quote! {
-            #d => Some(#name::#n)
+            if val == #name::#n as #prim_type {
+                return Some(#name::#n);
+            }
         }
     }).collect();
 
@@ -49,65 +50,8 @@ pub fn derive(ast: &syn::DeriveInput, mut prim_type: Option<syn::Type>) -> syn::
     }).collect();
     let all_variants_len = all_variants.len();
 
-    if prim_type.is_none() {
-        let min_ty: Vec<String> = v.iter().map(|d| {
-            if !d.suffix.is_empty() {
-                d.suffix.clone()
-            } else if d.negative {
-                let n = d.discriminant as i64;
-                if n < <i32>::min_value() as i64 {
-                    "i64".into()
-                } else {
-                    let n = -n;
-                    if n < <i16>::min_value() as i64 {
-                        "i32".into()
-                    } else if n < <i8>::min_value() as i64 {
-                        "i16".into()
-                    } else {
-                        "i8".into()
-                    }
-                }
-            } else {
-                let n = d.discriminant as u64;
-                if n > <u32>::max_value() as u64 {
-                    "u64".into()
-                } else if n > <u16>::max_value() as u64 {
-                    "u32".into()
-                } else if n > <u8>::max_value() as u64 {
-                    "u16".into()
-                } else {
-                    "u8".into()
-                }
-            }
-        }).collect();
-
-        // first mention, higher priority
-        let priority = [
-            "i64",
-            "i32",
-            "i16",
-            "i8",
-            "u64",
-            "u32",
-            "u16",
-            "u8"
-        ];
-        
-        let mut ty = "u8".to_string();
-        for t in min_ty {
-            if priority.iter().position(|&x| x == t).unwrap() < priority.iter().position(|&x| x == ty).unwrap() {
-                ty = t;
-            }
-        }
-        
-        prim_type = Some(syn::parse_str(&ty).expect("int ty parsing failed"));
-    }    
-
-    let prim_type = prim_type.expect("Unable to detect the primitive type for this enum.");
-
     let all_variants_const_ident = syn::Ident::new(&format!("{}_ALL", to_snake_case(&name.to_string())).to_uppercase(), Span::call_site());
     
-
     let mut str_format = {
         let to_display_str = to_display_str.clone();
         let all_variants_const_ident = all_variants_const_ident.clone();
@@ -158,10 +102,9 @@ pub fn derive(ast: &syn::DeriveInput, mut prim_type: Option<syn::Type>) -> syn::
 
             #[inline]
             fn from_primitive(val: #prim_type) -> Option<Self> {
-                match val {
-                    #(#from_primitive_match),* ,
-                    _ => None
-                }
+                #(#from_primitive_match)*
+
+                None
             }
 
             #[inline]
@@ -192,31 +135,9 @@ pub fn derive(ast: &syn::DeriveInput, mut prim_type: Option<syn::Type>) -> syn::
 }
 
 struct Variant {
-    variant: syn::Variant,
-    discriminant: u64,
-    negative: bool,
-    suffix: String
+    variant: syn::Variant
 }
 
-impl Variant {
-    fn get_discriminant(&self) -> proc_macro2::TokenStream {
-        let s = format!("{}{}",
-            self.discriminant,
-            self.suffix
-        );
-        let v: syn::LitInt = syn::parse_str(&s).expect("Error mid-parsing for disc value");
-
-        if self.negative {
-            quote! {
-                - #v
-            }
-        } else {
-            quote! { #v }
-        }
-    }
-}
-
-
 fn get_unitary_enum(input: &syn::DeriveInput) -> syn::Result<Vec<Variant>> {
     let data_enum = if let syn::Data::Enum(data_enum) = &input.data {
         data_enum
@@ -226,9 +147,6 @@ fn get_unitary_enum(input: &syn::DeriveInput) -> syn::Result<Vec<Variant>> {
 
     let mut r = Vec::new();
 
-    let mut d: Option<u64> = None;
-    let mut neg = false;
-
     for variant in &data_enum.variants {
         
         match variant.fields {
@@ -238,51 +156,9 @@ fn get_unitary_enum(input: &syn::DeriveInput) -> syn::Result<Vec<Variant>> {
             syn::Fields::Unit => {}
         }
 
-        let (discriminant, negative, suffix) = match &variant.discriminant {
-            Some((_, syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Int(ref lit_int), .. }))) => {
-                (lit_int.base10_parse()?, false, lit_int.suffix().into())
-            },
-            Some((_,
-                syn::Expr::Unary(syn::ExprUnary {
-                    op: syn::UnOp::Neg(_),
-                    expr,
-                    ..
-                }) 
-            )) => {
-
-                match **expr {
-                    syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Int(ref lit_int), .. }) => {
-                        (lit_int.base10_parse()?, true, lit_int.suffix().into())
-                    },
-                    _ => return Err(syn::Error::new(expr.span(), "Unsupported enum const expr (negated)"))
-                }
-            }
-            Some(_) => {
-                return Err(syn::Error::new(variant.span(), "Unsupported enum const expr"));
-            },
-            None => {
-                match d {
-                    None => (0, false, "".into()),
-                    Some(d) => {
-                        if neg {
-                            (d-1, d-1 != 0, "".into())
-                        } else {
-                            (d+1, false, "".into())
-                        }
-                    }
-                }
-            }
-        };
-
         r.push(Variant {
-            variant: variant.clone(),
-            discriminant,
-            negative,
-            suffix
+            variant: variant.clone()
         });
-
-        d = Some(discriminant);
-        neg = negative;                
     }
     
     Ok(r)
diff --git a/packed_struct_examples/Cargo.toml b/packed_struct_examples/Cargo.toml
index 794e3dc..85e8fa7 100644
--- a/packed_struct_examples/Cargo.toml
+++ b/packed_struct_examples/Cargo.toml
@@ -6,4 +6,4 @@ publish = false
 edition = "2018"
 
 [dependencies]
-packed_struct = { path = "../packed_struct/", version = "0.10", features = ["byte_types_64"] }
+packed_struct = { path = "../packed_struct/", version = "0.11", features = ["byte_types_64"] }
diff --git a/packed_struct_examples/src/example1.rs b/packed_struct_examples/src/example1.rs
index 752d7f4..fc10a06 100644
--- a/packed_struct_examples/src/example1.rs
+++ b/packed_struct_examples/src/example1.rs
@@ -26,7 +26,7 @@ pub struct ControlRegister {
     pub sensor_value: i16
 }
 
-#[derive(PrimitiveEnum, Debug, Copy, Clone, PartialEq)]
+#[derive(PrimitiveEnum_u8, Debug, Copy, Clone, PartialEq)]
 pub enum PowerMode {
     /// The sensor is turned off
     Off = 0,
diff --git a/packed_struct_nostd_tests/Cargo.toml b/packed_struct_nostd_tests/Cargo.toml
index 3fd6213..fbbec56 100644
--- a/packed_struct_nostd_tests/Cargo.toml
+++ b/packed_struct_nostd_tests/Cargo.toml
@@ -4,4 +4,4 @@ version = "0.1.0"
 authors = ["Rudi Benkovic <rudi.benkovic@gmail.com>"]
 
 [dependencies]
-packed_struct = { path = "../packed_struct/", version = "0.10", default-features = false }
\ No newline at end of file
+packed_struct = { path = "../packed_struct/", version = "0.11", default-features = false }
\ No newline at end of file
diff --git a/packed_struct_nostd_tests/src/lib.rs b/packed_struct_nostd_tests/src/lib.rs
index 780a670..b1d35ba 100644
--- a/packed_struct_nostd_tests/src/lib.rs
+++ b/packed_struct_nostd_tests/src/lib.rs
@@ -29,7 +29,7 @@ pub struct ControlRegister {
     pub sensor_value: i16
 }
 
-#[derive(PrimitiveEnum, Debug, Copy, Clone, PartialEq)]
+#[derive(PrimitiveEnum_u8, Debug, Copy, Clone, PartialEq)]
 pub enum PowerMode {
     /// The sensor is turned off
     Off = 0,
diff --git a/packed_struct_tests/Cargo.toml b/packed_struct_tests/Cargo.toml
index 7e37f6f..d99a187 100644
--- a/packed_struct_tests/Cargo.toml
+++ b/packed_struct_tests/Cargo.toml
@@ -6,6 +6,6 @@ publish = false
 edition = "2018"
 
 [dependencies]
-packed_struct = { path = "../packed_struct/", version = "0.10", features = ["byte_types_64", "use_serde"] }
+packed_struct = { path = "../packed_struct/", version = "0.11", features = ["byte_types_64", "use_serde"] }
 error-chain = "0.12.0"
 serde = "1.0"
\ No newline at end of file
diff --git a/packed_struct_tests/tests/primitive_enum_consts.rs b/packed_struct_tests/tests/primitive_enum_consts.rs
new file mode 100644
index 0000000..34a6dc4
--- /dev/null
+++ b/packed_struct_tests/tests/primitive_enum_consts.rs
@@ -0,0 +1,31 @@
+use packed_struct::prelude::*;
+
+pub const A1: u16 = 0;
+pub const A2: u16 = 1;
+pub const B1: u16 = 100;
+pub const C1: u16 = 200;
+
+#[derive(PrimitiveEnum_u16, Clone, Copy, Debug, PartialEq)]
+#[repr(u16)]
+pub enum ConstEnum {
+    A1 = A1,
+    A2 = A2,
+    B1 = B1,
+    B2,
+    C1 = C1,
+    C2,
+    D1 = 300,
+    D2
+}
+
+#[test]
+fn prim() {
+    assert_eq!(0, ConstEnum::A1.to_primitive());
+    assert_eq!(1, ConstEnum::A2.to_primitive());    
+    assert_eq!(100, ConstEnum::B1.to_primitive());
+    assert_eq!(101, ConstEnum::B2.to_primitive());
+    assert_eq!(200, ConstEnum::C1.to_primitive());
+    assert_eq!(201, ConstEnum::C2.to_primitive());
+    assert_eq!(300, ConstEnum::D1.to_primitive());
+    assert_eq!(301, ConstEnum::D2.to_primitive());
+}
\ No newline at end of file
diff --git a/packed_struct_tests/tests/primitive_enum_types.rs b/packed_struct_tests/tests/primitive_enum_types.rs
index 630bd74..a829746 100644
--- a/packed_struct_tests/tests/primitive_enum_types.rs
+++ b/packed_struct_tests/tests/primitive_enum_types.rs
@@ -1,52 +1,52 @@
 #![allow(clippy::enum_clike_unportable_variant)]
 use packed_struct::prelude::*;
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_u8, PartialEq, Debug, Clone, Copy)]
 pub enum EnumU8 {
     VariantMin = 0,
     VariantMax = 255
 }
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_u16, PartialEq, Debug, Clone, Copy)]
 pub enum EnumU16 {
     VariantMin = 0,
     VariantMax = 65535
 }
 
 #[repr(u32)]
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_u32, PartialEq, Debug, Clone, Copy)]
 pub enum EnumU32 {
     VariantMin = 0,
     VariantMax = 4294967295
 }
 
 #[cfg(target_pointer_width = "64")]
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_u64, PartialEq, Debug, Clone, Copy)]
 pub enum EnumU64 {
     VariantMin = 0,
     VariantMax = 1844674407370955165
 }
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_i8, PartialEq, Debug, Clone, Copy)]
 pub enum EnumI8 {
     VariantMin = -128,
     VariantMax = 127
 }
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_i16, PartialEq, Debug, Clone, Copy)]
 pub enum EnumI16 {
     VariantMin = -32768,
     VariantMax = 32767
 }
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_i32, PartialEq, Debug, Clone, Copy)]
 pub enum EnumI32 {
     VariantMin = -2147483648,
     VariantMax = 2147483647
 }
 
 #[cfg(target_pointer_width = "64")]
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_i64, PartialEq, Debug, Clone, Copy)]
 pub enum EnumI64 {
     VariantMin = -9223372036854775808,
     VariantMax = 9223372036854775807
diff --git a/packed_struct_tests/tests/primitive_enum_values.rs b/packed_struct_tests/tests/primitive_enum_values.rs
index 74232fe..25f765d 100644
--- a/packed_struct_tests/tests/primitive_enum_values.rs
+++ b/packed_struct_tests/tests/primitive_enum_values.rs
@@ -1,6 +1,6 @@
 use packed_struct::prelude::*;
 
-#[derive(PrimitiveEnum, PartialEq, Debug, Clone, Copy)]
+#[derive(PrimitiveEnum_i8, PartialEq, Debug, Clone, Copy)]
 pub enum EnumI8 {
     VariantMin = -128,